Re: "git-send-pack"

Here's another approach.

Teach the variants of git-pull to look for a file that names an
alternate repository
that should be used to get any object that is referenced in the repository, but
doesn't exist in it.

At least part of the problem for kernel.org is that there around 50 repositories
that are tracking the 2.6 kernel.  All of them have 50,000 objects that are
duplicates of each other ... and a few hundred 'unique' objects that belong
to just one repo, or are minimally shared.

If there was a way to specify an alternate repo, then a large GIT server like
kernel.org could set up a "git-history"[1] repo which each of the hosted repos
could point to.  Then a cron job could look for duplicates, and move them
off to the history area.

-Tony

[1] Different projects, like git and sparse, might never have any common
files with the Linux kernel ... but they can all share the same history.